(a) Technical Field
Exemplary embodiments described with reference to the accompanying drawings relate to an input current control method, a switch control circuit using the input current control method, and a power supply including the switch control circuit.
(b) Description of the Related Art
In a power supply, a peak of a current (i.e., a switch current) that flows to a power switch that controls powering is controlled to not exceed a predetermined current limit so as to control an input current of the power supply. In this case, the current limit is changed in order to constantly control the input current.
For example, the current limit may be a waveform of a sine wave function for constant control of the input current. However, although the current limit is changed, the input current cannot be precisely and constantly controlled, and distortion of the input current may occur at a zero crossing point of an input voltage. In addition, external elements (e.g., capacitors, resistors, and the like) of a switch control IC should be appropriately set so as to set the current limit.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.